SOLUTION: Xsq + Ysq = 9. X + Y = 2. Give two answers for X & Y

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Question 758206: Xsq + Ysq = 9. X + Y = 2. Give two answers for X & Y
Answer by kmadison(20) About Me  (Show Source):
You can put this solution on YOUR website!
2 equations, 2 unknowns:
Y+=+X+-+2
Now plug into the other equation:
X%5E2+%2B+Y%5E2+=+9 --> X%5E2+%2B+%28X-2%29%5E2+=+9
Expanding the 2nd portion:
X%5E2+%2B+%28X%5E2+-+4X+%2B+4%29+=+9
Now combine like terms and subtract 9 from both sides:
2X%5E2+-+4X+-+5+=+0
From here we use the quadratic formula to determine the 2 solutions for X:
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
From the formula we get 2 solutions for X: X+=+1-sqrt%287%2F2%29 and X+=+1+%2B+sqrt%287%2F2%29
Plug these into Y+=+X+-+2 and you will get your solutions for Y.